1. Field of the Invention
The present invention relates to a developer supply case which supplies a developer to an image forming apparatus such as an electrophotograph copying machine or a printer and an image forming apparatus to which the developer supply case is attachable.
2. Description of the Related Art
In a related art, a powdered developer is used as a developer for an image forming apparatus such as an electrophotograph copying machine or a printer. When the developer of the image forming apparatus is consumed, it is supplied to the image forming apparatus using a developer supply case.
The very fine powdered developer is scattered in the developer supplying operation, making the operator and surroundings dirty.
In recent years, a developer supply case is mostly used which is inserted into the image forming apparatus without opening its discharge port which is to be opened by operating an operation portion provided separately, and which supplies the stored developer to the image forming apparatus.
The developer supply case of the above constitution cannot supply the developer unless the discharge port opening operation is performed in the state that the discharge port of the developer supply case and the developer receiving port of the image forming apparatus body coincide with each other. Otherwise, the developer is scattered in the image forming apparatus body, making its interior dirty.
The discharge port of the developer supply case and the developer receiving port of the image forming apparatus body need to surely coincide with each other. As one method, in general, the developer supply case is completely inserted into the image forming apparatus so that the discharge port of the developer supply case and the developer receiving port of the image forming apparatus coincide with each other in size.
There has also been known a constitution in which a lock mechanism is provided in a sealing member which seals the discharge port of the developer supply case and is released after the developer supply case is inserted into the image forming apparatus body so that the discharge port of the developer supply case and the developer receiving port of the image forming apparatus body coincide with each other. In the position where the lock is released to open the discharge port, the discharge port of the developer supply case and the developer receiving port of the image forming apparatus body coincide with each other. This enables supply of the developer and prevents scattering of the developer in the image forming apparatus, which makes its interior dirty.
The developer supply case having the sealing member, as described above, is disclosed in Japanese Patent Application Laid-Open (JP-A) No. 2000-162861. A case shutter which seals the discharge port of the developer supply case can be slid in two directions. The case shutter can be slid in two directions so that it is slid in one direction and in the other direction. When the developer supply case is inserted into the image forming apparatus body, the case shutter abuts an engaging member provided in the image forming apparatus body so that it is slid in one direction. The case shutter can be slid in the other direction (shutter opening direction). The position of the discharge port of the developer supply case and the position of the developer receiving port of the image forming apparatus coincide with each other in the inserting direction. The shutter is opened in this state so that the discharge port of the developer supply case and the developer receiving port of the image forming apparatus coincide with each other.
In the constitution disclosed in JP-A No. 2000-162861, the developer supply case is inserted into the image forming apparatus body against an elastic member provided in the case shutter. Due to increase of the inserting force by the elastic force of the elastic member, the user can misunderstand that insertion of the developer supply case is completed and stop the inserting operation in the position. When the shutter is opened in this state, the shutter is regulated by the lock member provided in the shutter so as not to be slid. The user cannot open the developer supply case so that the developer cannot be supplied.
A constitution which promotes the inserting operation with respect to load variation during the inserting operation of the developer supply case is disclosed by Japanese Patent Application Laid-Open (JP-A) No. 9-90729.
JP-A No. 9-90729 discloses the constitution which has an exciting spring in a bottle holder of the image forming apparatus body so that the spring force of the exciting spring is larger than the operating force caused when the stopper of a toner bottle is fitted into the toner bottle.
The constitution disclosed in JP-A No. 9-90729 can be achieved by the rotation controlled bottle holder. It is not applicable to the constitution of front access in which the developer supply case is pushed into the front side of the image forming apparatus body for attachment. The constitution which uses the exciting spring increases the number of parts. The cost becomes a large burden on the constitution.
The developer supply case has been designed such that its inserting force is minimum. It has been considered that the reduced inserting force improves the operability of the developer supply case.